Control the led brightness (PWM output) using RPi

INSTALL DEPENDENCY:

1. Check any Python package installed in RPi
2. Open terminal paste below code.

python

python3

• If python, python3 and GPIO library of python is Not installed copy the below code and paste in terminal.

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install python
sudo apt-get install pyhton3
sudo apt-get install python-rpi.gpio python3-rpi.gpio

• Analog output basically PWM (Pulse Width Modulation) output.
• For more Details about PWM go through below calculation for how it produce variable voltage in GPIO pin of RPi using PWM method.

• led.GPIO.PWM(3,100) #Set  PWM output wih 100Hz Frequency
• 100Hz means 100cycles per sec.

REQUIRED COMPONENTS

1. Raspberry Pi (setup)- 1pic
2. Micro USB cable
3. Resistor 220E – 1pic
4. LED (3.5mm) -1pic
5. Breadboard- 1pic
6. Jumper wire – as per requirement

CIRCUIT CONNECTION:

 

CODE:

# Tested code by Robogenesis
import RPi.GPIO as GPIO 
import time

GPIO.setwarnings(False)
GPIO.setmode(GPIO.BOARD) #Board pin numbering
GPIO.setup(3, GPIO.OUT)  #Led is connected to Pin 3
led = GPIO.PWM(3,100) # set PWM output with 100Hz frequency

try :
    x=0
    while True :
            print ("increment")
            for x in range (0,100,1) :
                    led.ChangeDutyCycle(x)
                    time.sleep(0.02)
                    
            print ("Decrement")
            time.sleep(1)
            for x in range (100,0,-1) :
                    led.ChangeDutyCycle(x)
                    time.sleep(0.02)
            led.start(0)
except :
    led.stop()
    GPIO.cleanup()

OUTPUT:

Hava a Good Day!!